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101.
In studies of the effect of long or short-day photoperiod treatments on the qualitative gibberellin (GA) content of mature leaves of a facultative short-day (SD) strawberry cultivar (Fragaria × ananassa Duch. cv. Elsanta), GA1, GA8, GA17, GA19, GA20, GA29 and GA44 were identified by full-scan gas chromatography - mass spectrometry (GC-MS) in extracts from plants grown under long-day (LD) conditions, and GA1, GA5, GA8, GA19, GA20 and GA29 in similar extracts from plants subjected to eight SD cycles after growth under LD conditions. The early 13-hydroxylation GA biosynthetic pathway thus appeared to predominate, with the apparent absence of GA5 in LD and of GA17 and GA44 in SD extracts providing evidence of modulation of this pathway by photoperiod. A search, including GC-MS with selected ion monitoring, failed to detect GA3, or the polyhydroxylated GA85, GA86, GA87 or GA32 for which some extracts were specifically purified.This paper is respectfully dedicated to the memory of Gordon Browning, who died suddenly on the 1st July, 1993. He will be sorely missed, both as a friend and colleague. 相似文献
102.
Chafik Hdider Louis Philippe Vézina Yves Desjardins 《Plant Cell, Tissue and Organ Culture》1994,37(2):185-191
The uptake of 15NO3
- and 15NH4
+ has been examined in 5-,10- and 28-day-old micropropagated strawberry (Fragaria x ananassa Duch. cv. Kent) shoots rooted in one-half strength Murashige and Skoog (MS) liquid medium on cellulose plugs (Sorbarods). The results indicated that the plantlets absorbed both NO3
- and NH4
+ during the culture with a greater uptake of NH4
+ at 5 days of culture. Furthermore, a pronounced reduction in NO3
- and NH4
+ uptake at 10 and 28 days of culture was observed within 6 h of the short-term uptake study. This reduction could be explained by the low CO2 concentration in test tubes during the photoperiod, since no reduction in nitrogen uptake occurred in the CO2 enriched condition. The results are interpreted as an indication of the important role for photosynthetic CO2 fixation in the process of nitrogen uptake by the plantlets during the rooting stage.Contribution No. CRH 82, Centre de Recherche en Horticulture, F.S.A.A., Université Laval, Québec. 相似文献
103.
Markus S. Dillenberger Na Wei Jacob A. Tennessen Tia‐Lynn Ashman Aaron Liston 《American journal of botany》2018,105(5):862-874
Premise of the Study
Recurrent formation of polyploid taxa is a common observation in many plant groups. Haploid, cytoplasmic genomes like the plastid genome can be used to overcome the problem of homeologous genes and recombination in polyploid taxa. Fragaria (Rosaceae) contains several octo‐ and decaploid species. We use plastome sequences to infer the plastid ancestry of these taxa with special focus on the decaploid Fragaria cascadensis.Methods
We used genome skimming of 96 polyploid Fragaria samples on a single Illumina HiSeq 3000 lane to obtain whole plastome sequences. These sequences were used for phylogenetic reconstructions and dating analyses. Ploidy of all samples was inferred with flow cytometry, and plastid inheritance was examined in a controlled cross of F. cascadensis.Key Results
The plastid genome phylogeny shows that only the octoploid F. chiloensis is monophyletic, all other polyploid taxa were supported to be para‐ or polyphyletic. The decaploid Fragaria cascadensis has biparental plastid inheritance and four different plastid donors. Diversification of the F. cascadensis clades occurred in the last 230,000 years. The southern part of its distribution range harbors considerably higher genetic diversity, suggestive of a potential refugium.Conclusions
Fragaria cascadensis had at least four independent origins from parents with different plastomes. In contrast, para‐ and polyphyletic taxa of the octoploid Fragaria species are best explained by incomplete lineage sorting and/or hybridization. Biogeographic patterns in F. cascadensis are probably a result of range shift during the last glacial maximum. 相似文献104.
Two experiments are reported. In the first, six different strawberry genotypes were each grown in vitro on media containing five different concentrations of 6-benzylaminopurine (BAP) ranging from 0.5 M to 8.0 M. Responses of the genotypes to different BAP levels varied and the optimum levels for maximum proliferation were between 1 M and 8 M. In the second experiment the six genotypes were split into two groups of three and all crosses between the two groups were made. Seedlings from the nine progenies were then grown on media with the same five levels of BAP. Of the 12% of seedlings that did not proliferate, most were on media with the two lowest BAP levels (0.5 and 1.0 M). Seedlings from crosses involving the cv. Bogota proliferated least, while the three progenies with the breeding line ES652 as a parent had the highest mean proliferation rates. One cross, Bogota × Providence, had a particularly low mean proliferation rate. It was concluded that to optimize proliferation rate the medium must be tailored to the genotype. The best medium could not be reliably predicted from knowledge of the pedigree of a genotype. 相似文献
105.
The effectiveness of using honey bees and bumble bees to vector a commercial formulation of Trichoderma harzianum 1295-22 for the control of Botrytis cinerea on strawberries was evaluated from 1994 to 1997 in 2 strawberry fields at the New York State Agricultural Experiment Station in Geneva, New York and in 10 grower fields in eight counties of New York. Commercial bumble bee colonies were used to deliver the biocontrol agent in 1994 and 1995 and five-frame nuclear honey bee hives were used in 1995–1997. Each honey bee exiting the hive carried about 1 × 105 colony-forming units of T. harzianum, with the majority found on the bees' legs (58%). Flowers collected from the bee-delivered treatment generally had half the density of T. harzianum as those from the sprayed treatment. However, during the 4 years of this study, T. harzianum delivered by bumble bees or honey bees provided better Botrytis control than that applied as a spray. In addition, the bee-delivered T. harzianum provided the same or a better level of control of Botrytis as commercial fungicides applied at bloom. Strawberries collected from the bee-visited treatments averaged 22% more seeds and weighed between 26 and 40% more than berries in nonvisited treatments. The number of seeds per berry and berry weight were reduced by 7–12% in plots treated with fungicides and visited by bees, indicating that the use of some commercial fungicides at bloom may impact pollination and yield. Bee delivery of T. harzianum 1295-22 is a viable option for strawberry growers interested in controlling Botrytis with minimal fungicide use. 相似文献
106.
The endogenous gibberellins (GAs) in leaf tissues of two day-neutral cultivars (Rapella and Selva) of strawberry (Fragaria × ananassa Duch.) were analysed using combined gas chromatography -- mass spectrometry (GC-MS). Seven of the later members of the 13-hydroxylation GA biosynthetic pathway were identified, by comparison of Kovats retention indices and mass spectral data obtained for methyl ester trimethylsilyl ether derivatives, either with data obtained from authentic compounds or literature values. GA1, GA3, GA8, GA17, GA19, GA20 and GA29 were detected in extracts of both cultivars. 相似文献
107.
An efficient method of micropropagation based on an increased percentage survival of explants and reduced phenol-induced browning
in wild strawberry has been developed. Serial transfer of nodal explants was carried out at 24-, 48- and 96-h intervals. Nodal
segments cultured on Murashige and Skoog medium supplemented with 6-benzyladenine (4.0 μM) and α-naphthalene acetic acid (0.1
μM) gave the best (94.4%) explant establishment and shoot number (22.3) per explant. Of the cytokinins tested, 6-benzyladenine
was found more effective than kinetin and N6-(γ,γ dimethylallyamino) purine. Excised shoots rooted on half-strength agar-gelled medium with 1.0 μM α-naphthalene acetic
acid. Rooted shoots with fully expanded leaves acclimatized successfully and about 70% of plantlets survived ex vitro.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
108.
109.
110.
ANDREW KENIRY CLARE J. HOPKINS ERICA JEWELL BRUCE MORRISON GERMAN C. SPANGENBERG DAVID EDWARDS JACQUELINE BATLEY 《Molecular ecology resources》2006,6(2):319-322
The availability of expressed sequence data derived from gene discovery programmes enables mining for simple sequence repeats (SSRs), providing useful genetic markers for crop improvement. These markers are inexpensive, require minimal labour to produce and can frequently be associated with functionally annotated genes. This study reports on the development and characterization of expressed sequence tag (EST)–SSR markers in the cultivated strawberry, Fragaria×ananassa. Fourteen primer pairs were assessed for polymorphism in 13 F.×ananassa genotypes. The markers show reliable amplification and considerable polymorphism, demonstrating the utility of EST–SSRs for genetic analysis of commercial strawberry germplasm. 相似文献